Don't forget, this game is still super new.
You may be getting better, but so are everyone else. Don't be put off, playing the numbers game - you'll soon be getting more kills/wins as long as you keep improving. Watch some youtube videos of suggestions/tips, try to stick with doing certain things, like fighting from cover and healing regularly, short bursts, good recoil control, sliding where possible, etc etc..
I got 2 wins this morning on PC and that was with pad. I've noticed when i'm aiming on PC using mnk I always seem to be aiming to one side of the person i'm trying to hit for some reason like i'm trying to predict the way they are going to move or something.